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                    updateSuspenseComponent
            
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                    updatePortalComponent
            
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                    commitPlacement
            
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                                <h1 id="&#x4E8B;&#x4EF6;&#x89E6;&#x53D1;">&#x4E8B;&#x4EF6;&#x89E6;&#x53D1;</h1><p>&#x4E4B;&#x524D;&#x6211;&#x4EEC;&#x5DF2;&#x7ECF;&#x8BB2;&#x4E86;&#x4E8B;&#x4EF6;&#x662F;&#x7ED1;&#x5B9A;&#x5728;<code>container</code>&#x4E0A;&#x7684;&#xFF0C;&#x90A3;&#x4E48;&#x5177;&#x4F53;&#x4E8B;&#x4EF6;&#x89E6;&#x53D1;&#x7684;&#x65F6;&#x5019;&#x662F;&#x5982;&#x4F55;&#x6D3E;&#x53D1;&#x5230;&#x5177;&#x4F53;&#x7684;&#x76D1;&#x542C;&#x8005;&#x4E0A;&#x7684;&#x5462;&#xFF1F;&#x8FD9;&#x91CC;&#x6211;&#x4EEC;&#x5C31;&#x5F80;&#x4E0B;&#x770B;&#xFF0C;&#x5047;&#x8BBE;&#x6211;&#x4EEC;&#x7ED1;&#x5B9A;&#x7684;&#x662F;<code>dispatchInteractiveEvent</code>&#x65B9;&#x6CD5;&#xFF0C;&#x90A3;&#x4E48;&#x6211;&#x4EEC;&#x6765;&#x770B;&#x770B;&#x4ED6;&#x7684;&#x5B9E;&#x73B0;&#x8FC7;&#x7A0B;&#xFF1A;</p><pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">dispatchInteractiveEvent</span>(<span class="hljs-params">topLevelType, nativeEvent</span>) </span>{
  interactiveUpdates(dispatchEvent, topLevelType, nativeEvent)
}

<span class="hljs-comment">// &#x6765;&#x81EA;&apos;events/ReactGenericBatching&apos;</span>
<span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">interactiveUpdates</span>(<span class="hljs-params">fn, a, b</span>) </span>{
  <span class="hljs-keyword">return</span> _interactiveUpdatesImpl(fn, a, b)
}
<span class="hljs-keyword">let</span> _interactiveUpdatesImpl = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">fn, a, b</span>) </span>{
  <span class="hljs-keyword">return</span> fn(a, b)
}</code></pre>
<p>&#x8FD9;&#x91CC;&#x7B80;&#x5355;&#x6765;&#x8BF4;&#x5C31;&#x662F;&#x8C03;&#x7528;&#x4E86;<code>dispatchEvent(topLevelType, nativeEvent)</code>&#xFF0C;<code>topLevelType</code>&#x5C31;&#x662F;<code>onClick</code>&#x8FD9;&#x7C7B;&#x5F97; React &#x4E2D;&#x5F97;<code>props</code>&#x540D;&#x5B57;&#xFF0C;<code>nativeEvent</code>&#x5C31;&#x662F; DOM &#x4E8B;&#x4EF6;&#x5BF9;&#x8C61;&#x3002;&#x90A3;&#x4E48;&#x6211;&#x4EEC;&#x6765;&#x770B;<code>dispatchEvent</code></p><pre><code class="lang-js"><span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">dispatchEvent</span>(<span class="hljs-params">
  topLevelType: DOMTopLevelEventType,
  nativeEvent: AnyNativeEvent,
</span>) </span>{
  <span class="hljs-keyword">const</span> nativeEventTarget = getEventTarget(nativeEvent)
  <span class="hljs-comment">// &#x627E;&#x5230;&#x70B9;&#x51FB;&#x4E8B;&#x4EF6;&#x89E6;&#x53D1;&#x7684;&#x539F;&#x59CB;&#x8282;&#x70B9;&#x6700;&#x8FD1;&#x7684;Fiber&#x5BF9;&#x8C61;</span>
  <span class="hljs-comment">// &#x6839;&#x636E;&#x8BBE;&#x7F6E;&#x5728;DOM&#x8282;&#x70B9;&#x4E0A;&#x7684;`internalInstanceKey`&#x6765;&#x5BFB;&#x627E;</span>
  <span class="hljs-keyword">let</span> targetInst = getClosestInstanceFromNode(nativeEventTarget)
  <span class="hljs-keyword">if</span> (
    targetInst !== <span class="hljs-literal">null</span> &amp;&amp;
    <span class="hljs-keyword">typeof</span> targetInst.tag === <span class="hljs-string">&apos;number&apos;</span> &amp;&amp;
    !isFiberMounted(targetInst)
  ) {
    targetInst = <span class="hljs-literal">null</span>
  }

  <span class="hljs-comment">// pool</span>
  <span class="hljs-keyword">const</span> bookKeeping = getTopLevelCallbackBookKeeping(
    topLevelType,
    nativeEvent,
    targetInst,
  )

  <span class="hljs-keyword">try</span> {
    batchedUpdates(handleTopLevel, bookKeeping)
  } <span class="hljs-keyword">finally</span> {
    releaseTopLevelCallbackBookKeeping(bookKeeping)
  }
}

<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">getEventTarget</span>(<span class="hljs-params">nativeEvent</span>) </span>{
  <span class="hljs-keyword">let</span> target = nativeEvent.target || nativeEvent.srcElement || <span class="hljs-built_in">window</span>

  <span class="hljs-keyword">if</span> (target.correspondingUseElement) {
    target = target.correspondingUseElement
  }
  <span class="hljs-keyword">return</span> target.nodeType === TEXT_NODE ? target.parentNode : target
}</code></pre>
<p>&#x8FD9;&#x91CC;&#x4E3B;&#x8981;&#x521B;&#x5EFA;&#x4E86;<code>bookKeeping</code>&#x5BF9;&#x8C61;&#xFF0C;&#x5305;&#x542B;&#x4E86;<strong>&#x4E8B;&#x4EF6;&#x540D;&#x79F0;&#xFF0C;&#x539F;&#x59CB;&#x4E8B;&#x4EF6;&#x5BF9;&#x8C61;&#xFF0C;&#x4EE5;&#x53CA;&#x6700;&#x8FD1;&#x7684;<code>Fiber</code>&#x5BF9;&#x8C61;</strong>&#xFF0C;&#x7136;&#x540E;&#x8C03;&#x7528;<code>batchedUpdates</code>&#xFF0C;&#x6211;&#x4EEC;&#x6765;&#x770B;&#x770B;&#x8FD9;&#x4E2A;&#x65B9;&#x6CD5;&#xFF1A;</p><pre><code class="lang-js"><span class="hljs-comment">// &#x6765;&#x81EA;&apos;events/ReactGenericBatching&apos;</span>
<span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">batchedUpdates</span>(<span class="hljs-params">fn, bookkeeping</span>) </span>{
  <span class="hljs-keyword">if</span> (isBatching) {
    <span class="hljs-keyword">return</span> fn(bookkeeping)
  }
  isBatching = <span class="hljs-literal">true</span>
  <span class="hljs-keyword">try</span> {
    <span class="hljs-keyword">return</span> _batchedUpdatesImpl(fn, bookkeeping)
  } <span class="hljs-keyword">finally</span> {
    isBatching = <span class="hljs-literal">false</span>
    <span class="hljs-keyword">const</span> controlledComponentsHavePendingUpdates = needsStateRestore()
    <span class="hljs-keyword">if</span> (controlledComponentsHavePendingUpdates) {
      _flushInteractiveUpdatesImpl()
      restoreStateIfNeeded()
    }
  }
}

<span class="hljs-keyword">let</span> _batchedUpdatesImpl = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">fn, bookkeeping</span>) </span>{
  <span class="hljs-keyword">return</span> fn(bookkeeping)
}</code></pre>
<p>&#x5176;&#x5B9E;&#x5C31;&#x662F;&#x8BBE;&#x7F6E;&#x4E86;&#x4E00;&#x4E0B;<code>isBatching</code>&#x8FD9;&#x4E2A;&#x516C;&#x5171;&#x53D8;&#x91CF;&#xFF0C;&#x7136;&#x540E;&#x8C03;&#x7528;<code>handleTopLevel</code>&#xFF0C;&#x63A5;&#x7740;&#x770B;</p><pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">handleTopLevel</span>(<span class="hljs-params">bookKeeping</span>) </span>{
  <span class="hljs-keyword">let</span> targetInst = bookKeeping.targetInst

  <span class="hljs-keyword">let</span> ancestor = targetInst
  <span class="hljs-keyword">do</span> {
    <span class="hljs-keyword">if</span> (!ancestor) {
      bookKeeping.ancestors.push(ancestor)
      <span class="hljs-keyword">break</span>
    }
    <span class="hljs-keyword">const</span> root = findRootContainerNode(ancestor)
    <span class="hljs-keyword">if</span> (!root) {
      <span class="hljs-keyword">break</span>
    }
    bookKeeping.ancestors.push(ancestor)
    ancestor = getClosestInstanceFromNode(root)
  } <span class="hljs-keyword">while</span> (ancestor)

  <span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> i = <span class="hljs-number">0</span>; i &lt; bookKeeping.ancestors.length; i++) {
    targetInst = bookKeeping.ancestors[i]
    runExtractedEventsInBatch(
      bookKeeping.topLevelType,
      targetInst,
      bookKeeping.nativeEvent,
      getEventTarget(bookKeeping.nativeEvent),
    )
  }
}

<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">findRootContainerNode</span>(<span class="hljs-params">inst</span>) </span>{
  <span class="hljs-keyword">while</span> (inst.return) {
    inst = inst.return
  }
  <span class="hljs-keyword">if</span> (inst.tag !== HostRoot) {
    <span class="hljs-keyword">return</span> <span class="hljs-literal">null</span>
  }
  <span class="hljs-keyword">return</span> inst.stateNode.containerInfo
}</code></pre>
<p>&#x8FD9;&#x91CC;&#x7B80;&#x5355;&#x6765;&#x8BF4;&#x5982;&#x679C;&#x76EE;&#x6807;&#x8282;&#x70B9;&#x5728;<code>portal</code>&#x5185;&#xFF0C;&#x90A3;&#x4E48;&#x9700;&#x8981;&#x5305;&#x62EC;<code>portal</code>&#x5916;&#x90E8;&#x7684;&#x8282;&#x70B9;&#xFF0C;&#x5BF9;&#x4E8E;&#x6BCF;&#x4E2A;<code>ancestor</code>&#xFF0C;&#x8C03;&#x7528;<code>runExtractedEventsInBatch</code></p><pre><code class="lang-js"><span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">runExtractedEventsInBatch</span>(<span class="hljs-params">
  topLevelType: TopLevelType,
  targetInst: null | Fiber,
  nativeEvent: AnyNativeEvent,
  nativeEventTarget: EventTarget,
</span>) </span>{
  <span class="hljs-keyword">const</span> events = extractEvents(
    topLevelType,
    targetInst,
    nativeEvent,
    nativeEventTarget,
  )
  runEventsInBatch(events, <span class="hljs-literal">false</span>)
}

<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">extractEvents</span>(<span class="hljs-params">
  topLevelType: TopLevelType,
  targetInst: null | Fiber,
  nativeEvent: AnyNativeEvent,
  nativeEventTarget: EventTarget,
</span>): <span class="hljs-title">Array</span>&lt;<span class="hljs-title">ReactSyntheticEvent</span>&gt; | <span class="hljs-title">ReactSyntheticEvent</span> | <span class="hljs-title">null</span> </span>{
  <span class="hljs-keyword">let</span> events = <span class="hljs-literal">null</span>
  <span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> i = <span class="hljs-number">0</span>; i &lt; plugins.length; i++) {
    <span class="hljs-comment">// Not every plugin in the ordering may be loaded at runtime.</span>
    <span class="hljs-keyword">const</span> possiblePlugin: PluginModule&lt;AnyNativeEvent&gt; = plugins[i]
    <span class="hljs-keyword">if</span> (possiblePlugin) {
      <span class="hljs-keyword">const</span> extractedEvents = possiblePlugin.extractEvents(
        topLevelType,
        targetInst,
        nativeEvent,
        nativeEventTarget,
      )
      <span class="hljs-keyword">if</span> (extractedEvents) {
        events = accumulateInto(events, extractedEvents)
      }
    }
  }
  <span class="hljs-keyword">return</span> events
}</code></pre>
<p>&#x8FD9;&#x91CC;&#x5F00;&#x59CB;&#x751F;&#x6210;&#x4E8B;&#x4EF6;&#xFF0C;&#x8C03;&#x7528;&#x6BCF;&#x4E2A;<code>plugin</code>&#x7684;<code>extractEvents</code>&#x65B9;&#x6CD5;&#x6765;&#x751F;&#x4EA7;&#x4E8B;&#x4EF6;&#xFF0C;&#x5E76;&#x8C03;&#x7528;<code>accumulateInto</code>&#x6765;&#x5408;&#x5E76;&#x4E8B;&#x4EF6;</p><pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">accumulateInto</span>&lt;<span class="hljs-title">T</span>&gt;(<span class="hljs-params">
  current: ?(Array&lt;T&gt; | T</span>),
  <span class="hljs-title">next</span>: <span class="hljs-title">T</span> | <span class="hljs-title">Array</span>&lt;<span class="hljs-title">T</span>&gt;,
): <span class="hljs-title">T</span> | <span class="hljs-title">Array</span>&lt;<span class="hljs-title">T</span>&gt; </span>{
  <span class="hljs-keyword">if</span> (current == <span class="hljs-literal">null</span>) {
    <span class="hljs-keyword">return</span> next
  }

  <span class="hljs-keyword">if</span> (<span class="hljs-built_in">Array</span>.isArray(current)) {
    <span class="hljs-keyword">if</span> (<span class="hljs-built_in">Array</span>.isArray(next)) {
      current.push.apply(current, next)
      <span class="hljs-keyword">return</span> current
    }
    current.push(next)
    <span class="hljs-keyword">return</span> current
  }

  <span class="hljs-keyword">if</span> (<span class="hljs-built_in">Array</span>.isArray(next)) {
    <span class="hljs-keyword">return</span> [current].concat(next)
  }

  <span class="hljs-keyword">return</span> [current, next]
}</code></pre>
<p>&#x8FD9;&#x4E2A;&#x65B9;&#x6CD5;&#x4E3B;&#x8981;&#x662F;&#x5224;&#x65AD;&#x5F53;&#x524D;&#x7684;<code>events</code>&#x548C;<code>next</code>&#x5BF9;&#x5E94;&#x7684;&#x521A;&#x4EA7;&#x751F;&#x7684;<code>event</code>&#xFF0C;&#x56E0;&#x4E3A;&#x4ED6;&#x4EEC;&#x90FD;&#x53EF;&#x80FD;&#x662F;&#x5355;&#x4E2A;&#x4E8B;&#x4EF6;&#x6216;&#x8005;&#x662F;&#x6570;&#x7EC4;&#xFF0C;&#x6700;&#x7EC8;&#x76EE;&#x7684;&#x662F;&#x8981;&#x8FBE;&#x6210;&#x6570;&#x7EC4;&#x5408;&#x5E76;&#xFF0C;&#x6700;&#x7EC8;&#x8FD4;&#x56DE;&#x4E00;&#x4E2A;&#x6570;&#x7EC4;&#xFF0C;&#x4E8B;&#x4EF6;&#x751F;&#x4EA7;&#x597D;&#x4E4B;&#x540E;&#xFF0C;&#x8C03;&#x7528;<code>runEventsInBatch</code>&#xFF0C;&#x63A5;&#x4E0B;&#x53BB;&#x770B;</p><pre><code class="lang-js"><span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">runEventsInBatch</span>(<span class="hljs-params">
  events: Array&lt;ReactSyntheticEvent&gt; | ReactSyntheticEvent | null,
  simulated: boolean,
</span>) </span>{
  <span class="hljs-keyword">if</span> (events !== <span class="hljs-literal">null</span>) {
    eventQueue = accumulateInto(eventQueue, events)
  }

  <span class="hljs-keyword">const</span> processingEventQueue = eventQueue
  eventQueue = <span class="hljs-literal">null</span>

  <span class="hljs-keyword">if</span> (!processingEventQueue) {
    <span class="hljs-keyword">return</span>
  }

  <span class="hljs-keyword">if</span> (simulated) {
    forEachAccumulated(
      processingEventQueue,
      executeDispatchesAndReleaseSimulated,
    )
  } <span class="hljs-keyword">else</span> {
    forEachAccumulated(
      processingEventQueue,
      executeDispatchesAndReleaseTopLevel,
    )
  }
  rethrowCaughtError()
}</code></pre>
<p><code>simulated</code>&#x4F20;&#x5165;&#x7684;&#x662F;<code>false</code>&#xFF0C;&#x6240;&#x4EE5;&#x8C03;&#x7528;&#x7684;&#x662F;<code>executeDispatchesAndReleaseTopLevel</code></p><pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">forEachAccumulated</span>&lt;<span class="hljs-title">T</span>&gt;(<span class="hljs-params">
  arr: ?(Array&lt;T&gt; | T</span>),
  <span class="hljs-title">cb</span>: (<span class="hljs-params">elem: T</span>) =&gt; <span class="hljs-title">void</span>,
  <span class="hljs-title">scope</span>: ?<span class="hljs-title">any</span>,
) </span>{
  <span class="hljs-keyword">if</span> (<span class="hljs-built_in">Array</span>.isArray(arr)) {
    arr.forEach(cb, scope)
  } <span class="hljs-keyword">else</span> <span class="hljs-keyword">if</span> (arr) {
    cb.call(scope, arr)
  }
}

<span class="hljs-keyword">const</span> executeDispatchesAndReleaseTopLevel = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">e</span>) </span>{
  <span class="hljs-keyword">return</span> executeDispatchesAndRelease(e, <span class="hljs-literal">false</span>)
}

<span class="hljs-keyword">const</span> executeDispatchesAndRelease = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">
  event: ReactSyntheticEvent,
  simulated: boolean,
</span>) </span>{
  <span class="hljs-keyword">if</span> (event) {
    executeDispatchesInOrder(event, simulated)

    <span class="hljs-keyword">if</span> (!event.isPersistent()) {
      event.constructor.release(event)
    }
  }
}

<span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">executeDispatchesInOrder</span>(<span class="hljs-params">event, simulated</span>) </span>{
  <span class="hljs-keyword">const</span> dispatchListeners = event._dispatchListeners
  <span class="hljs-keyword">const</span> dispatchInstances = event._dispatchInstances
  <span class="hljs-keyword">if</span> (<span class="hljs-built_in">Array</span>.isArray(dispatchListeners)) {
    <span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> i = <span class="hljs-number">0</span>; i &lt; dispatchListeners.length; i++) {
      <span class="hljs-keyword">if</span> (event.isPropagationStopped()) {
        <span class="hljs-keyword">break</span>
      }
      <span class="hljs-comment">// Listeners and Instances are two parallel arrays that are always in sync.</span>
      executeDispatch(
        event,
        simulated,
        dispatchListeners[i],
        dispatchInstances[i],
      )
    }
  } <span class="hljs-keyword">else</span> <span class="hljs-keyword">if</span> (dispatchListeners) {
    executeDispatch(event, simulated, dispatchListeners, dispatchInstances)
  }
  event._dispatchListeners = <span class="hljs-literal">null</span>
  event._dispatchInstances = <span class="hljs-literal">null</span>
}

<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">executeDispatch</span>(<span class="hljs-params">event, simulated, listener, inst</span>) </span>{
  <span class="hljs-keyword">const</span> type = event.type || <span class="hljs-string">&apos;unknown-event&apos;</span>
  event.currentTarget = getNodeFromInstance(inst)
  invokeGuardedCallbackAndCatchFirstError(type, listener, <span class="hljs-literal">undefined</span>, event)
  event.currentTarget = <span class="hljs-literal">null</span>
}</code></pre>
<p><code>_dispatchListeners</code>&#x548C;<code>_dispatchInstances</code>&#x662F;&#x5728;&#x751F;&#x6210;&#x4E8B;&#x4EF6;&#x5BF9;&#x8C61;&#x7684;&#x65F6;&#x5019;&#x8D4B;&#x503C;&#x7684;&#xFF0C;&#x5728;<code>executeDispatchesInOrder</code>&#x4E2D;&#x6211;&#x4EEC;&#x5C31;&#x6309;&#x7167;&#x987A;&#x5E8F;&#x6267;&#x884C;&#x4E86;&#x6240;&#x6709;&#x76D1;&#x542C;&#x7684;&#x4E8B;&#x4EF6;&#x4E86;&#x3002;</p>
                                
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